Server-authoritative, offline-first SQL sync you can operate. Clients keep a real local SQLite database (OPFS in the browser, native SQLite elsewhere), writes go through an optimistic outbox, and one ordered commit log on the server stays the source of truth.
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bun create syncular-app my-appHow the repo is built
- Spec-first: SPEC.md is normative and spec/vectors/ are golden fixtures; when spec and code disagree, the code changes. Two cores (TypeScript and Rust) are kept in lockstep by an implementation-agnostic conformance suite.
- Test doctrine: loopback in-memory transport for integration scenarios; fault injection at the transport interface; tests wait on explicit readiness signals (sleeps are banned); real-socket tests few and quarantined. See packages/conformance.
- One good path: the browser persists to OPFS and reports unsupported environments as errors; sync runs over the WebSocket.
Layout
Path What it is packages/core Protocol codecs, shared types, vector round-trip packages/server handleSyncRequest(bytes, ctx) + storage/auth interfaces (SQLite, Postgres, D1) packages/server-hono, packages/server-workers Framework bindings (Hono, Cloudflare Workers) packages/web-client @syncular/client: TS client core on @sqlite.org/sqlite-wasm packages/react React hooks over the client packages/typegen Schema IR + TypeScript emitter, named queries (cargo-free) packages/crypto, packages/crdt-yjs Per-column E2EE primitives, Yjs CRDT mergers packages/testing @syncular/testkit: in-memory loopback of real server + clients packages/conformance Scenario runner both cores must pass rust/ The Rust client core and its C-ABI FFI crate bindings/ Tauri, React Native, Swift, Kotlin, Flutter apps/docs The docs site (syncular.dev)Commands
bun install bun run check # typecheck + lint + testContributing
Read AGENTS.md first. The doctrine in it (spec-first, no fallbacks, no timers in tests, cross-core parity) applies to human and machine contributors alike.
On AI assistance: LLMs are welcome for tests, reproductions, benchmarks, docs, and production code. Review, understand, and iterate on everything you submit, and be ready to defend every line; production code gets the strictest review. In syncular's own development, LLM assistance is used mainly for writing tests and iterating over technical concepts, under that same review bar. Low-effort machine-generated PRs, issues, and comments are closed without comment. The full policy and the plain-text docs bundle for agents live at syncular.dev/llms.
